Artificial limb.



A. ZUMAGLINI.

ARTIFICIAL LIMB. APPLICATION F| LED APR. I0. 1917- I llfimwo Patented 00w. 1, 1918.

A Tram/5m rarnir snip.

ANTONIO ZUMAGLINI, OF TURIN, ITALY.

ARTIFICIAL LIMB.

resents.

To all whom it may concern:

Be it known that I, Dr. ANTONIO ZUMA- GLINI, a subject of the King of Italy, and residing in Turin, Italy, have invented certain new and useful Improvements in Artificial Limbs, of which the following is a full, true, and exact specification.

The present invention relates to'improvements in spring hinged knees for artificial legs to be used by. the mutilated, which are made of cast metal, and possesses the characteristics that it can be regulated, acts automatically, and always retains its natural form regardless of the position of thehinge.

The invention is capable of expression in difierent ways, a practical form of which is disclosed in the accompanying drawings forming part hereof, and in which Figure 1 is sectional elevation of the knee portion of an artificial leg,

Fig. 2 is a detached view of a cushioning device used with my improvements,

Fig. 3 is an enlarged sectional view showing connection 01": cushioning devices.

Referring more particularly to the drawing it will be seen that the upper part of the hinge 1 carried by the thigh member of the leg is connected to the lower portion and is also provided with two rocker pins 2 having rounded lower faces and which must be strong enough to support the weight of the whole body; said rocker pins bear on two suitable bearing blocks 3 fixed on the upper end of the lower portion 4: of the leg.

The upper and lower members of the leg are so constructed that they can readily fit, one in the other during the rocking or rotation of portion '1 on the pins 2. The portions which slide past each other are formed by approximately identical sections of a spherical form having the form of a lmee and their center of rotation being the same as the center of the rocker pins 2. The upper member 1 has a jointed stop device 5, which on account of its own weight normally bears within the hole 6 in the member 2 so as to prevent the rotation of the two sections, thereby making a substantially rigid leg.

By means of a small stop 7, controlled from the exterior of the leg, a button 8 at the outer end of the stop device 5 can be kept elevated thereby allowing the operation of the hinged joint.

The upper member carries a horizontal pin 9 to which is pivotally connected the upper Specification of Letters Patent.

Patented Oct. 1,1918.

Application filed April 10, 1917. Serial No. 161,100.

end of a spring device (see Fig. 2) comprising a metallic casing 11 containing a coiled spring 20 compressed to a suitable starting pressure between the casing closures 12 and 13. Within the spring 20 is placed a stem 14 having a lower projecting portion 15 which is screw-threaded, while at the opposite or upper end, it has the projection or head 16. By means of a thumb screw 17, or other suitable device, the compression of the spring can be increased or diminished thus changing the tension of the spring and regulating the tension and movement of the joint between the upper and lower sections of the leg. When the leg is flexed the casing 12 of the spring device abuts the upper wall of the lower leg member, below the pin 9 carried by the upper member.

In order to prevent a too rapid extension movement of the lower member of the leg, I provide another spring device designated as 18 in Fig. 3 which includes a guide element through which passes a bolt, to the upper end of which is attached the lower end of a flexible member 19, the upper end of which is connected to upper member of the leg, as clearly shown in Fig. 3. The lower end of the bolt is shown as threaded at its lower end upon which is threaded a winged nut, and surrounding the bolt between the winged nut and the guide element, a coiled spring is held, the tension of which can be regulated by said winged nut. The function of the spring device just described is that of a brake which acts gradually though strongly when the leg is almost fully extended, and thus renders its movement absolutely similar to a natural movement of the natural leg. This spring device 18 acts as follows: In the final movement of rotation of the leg, the upper member 1 pulls on the small chain 19 which in turn compresses the compensating spring 18 between the guide element and the winged nut in such a manner that the action oi the compensating spring and coiled spring 20 in casing 11 is gradually balanced and equalized, and the lower leg member finishes its movement slowly and easily and without jar or jerk.

As before stated the tension of spring 18 can be regulated as well as that of spring 20 so that the movement of the leg will be automatically regulated.

What I claim is:

1. An artificial leg including independent upper and lower members, the upper member having a knee portion having a spherical socket therein, the lower member having a spherical extension at its upper end adapted to fit and oscillate within said socket, and means for resiliently connecting said upper and lower members.

2. An artificial leg including independent upper and lower members, the upper member having a spherical socket in its lower end and a rocker member adjacent to said socket, the lower member having a mating spherical projection at its upper end fitting and adapted to oscillate in said socket, a bearing member to the rear of said projection and adapted to support the rocker member of the upper leg member, resilient means for connecting said upper and lower leg members, and means for controlling and regulating the relative movement of said members.

3. An artificial leg including independently movable upper and lower members, the upper member having at lts lower end a lower members eccentrically ofthe rocker coupling joint. i

In witness whereof, I have hereunto signed my name in the presence of two subscribing witnesses.

DR. HON. ANTONIO ZUMAGLINI.

Witnesses:

TRZ. ANDREA LUINs, GIUsnrPn AIBs.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

